Rotary car dumper



Jap. 7, 1964 M. w. CLARK ROTARY CAR DUMPEF.

Filed March 22, 1961 9 Sheets-Sheet l INVENTOR. MILTON W CLARK BY 7W, uva@ mvw, f- 7 I AT TQRNEYS Jan. 7, 1964 M. w. CLARK 3,116,843

ROTARY CAR DUMPER Filed March 22, 1961 9 Sheets-Sheet 2 N l l HIWIIIHIIIIIIIIIII Q HIIIIIIIIIIIHIIIIII FIG. 2

INVENTOR. MILTON W. CLARK BY 7pm/MIMI 74 ATTORNEYS Jan. 7, 1964 M. w. CLARK 3,116,843

ROTARY CAR BUMPER Filed March 22, 1961 9 sheets-sheet s FIG. 3

IN VEN TOR. MILTON W. CLARK fa/LLZMQ ATTORNEYS Jan. 7, 1964 Filed March 22. 1961 M. w. CLARK 3,116,843

ROTARY CAR DUMPER INVENTOR. MLTON W. CLARK ATTORNEYS Jan. 7, 1964 I M. w. CLARK 3,116,843

` ROTARY CAR DUMPER Filed March 22, 1961 9 Sheets-Sheet 5 FIG. 8

FIG. 6

INVENTOR. MILTON W. CLARK ATTORNEYS Jan. 7, 1964 M. W. CLARK ROTARY CAR DUMPER 9 She-etS-Sheet 6 E iled March 22, 1961 INVENTOR M|LToN w. CLARK ATTORNEYS Jan. 7, 1964 M. w. CLARK ROTARY CAR BUMPER 9 Sheets-Sheet 7 FIG. 11 I2 Filed March 22, 1961 FIG. 12

INVEN TOR MILTON W. CLARK Jan. 7, 1964 M. w. CLARK 3,116,343

ROTARY CAR DUMPER Filed March 22, 1 .961 9 Sheets-Sheet 8 Y :im

lHHM..

FlG. 17

INVEN TOR.

MILTON W. CLARK ATTORNEYS Jan. 7, 1964 M. w` CLARK v 3,116,843

ROTARY CAR BUMPER Filed March 22, 1961 v 9 Sheets-Sheet 9 FIG. 23

INVENTOR. M|| ToN w. cLAR x ATTORNEYS United States Patent "ice 3,116,843 ROTARY CAR BUMPER Milton W. Clark, Rockville Centre, N.Y., asslgnorto The Anaconda Company, a corporation of Montana Filed Mar. 22, 1961, Ser. No. 97,576 6 Claims. (Cl. 214-55) This invention relates to rotary dumpers for unloading open railway cars and the like by revolving them into inverted position and, more particularly, to improved means for holding the car on a' platen within the'dumper during yunloading and for realigning the platen both-long1 tudinally and laterally after unloading.

Rotary car dumpers generally include a heavy frame or cradle within which a car-supporting platen is mounted. In the upright position of the cradle, movable tracks on the platen should be aligned with stationary yard tracks so that one or more cars can be rolled onto the platen. The car is then clamped in some manner against the rails and the heavy cradle is rotated until the car is substantially inverted and its contents fall into a hopper beneath the cradle. Upon rotation of the cradle back to upright position, the tracks-should come into realignment so that the car can be moved off the platen onto the yard rails. In general, a rotary car dumper can be considered satisfactory if over long periods of time and with out extensive maintenance it can repeat this cycle of operation and each time return to a properly aligned position.

One of the major causes of misalignment in conventional rotary dumpers-is that the combined' effect of the enormous loads onv the cradle plus the impact stresses occurring during rotation of the cradle eventually strain' the structure to the point where critical dimensional changes take place. For example, along a cradle length of many feet, it is not unusual for the platen tracks to become misaligned an inch or so relative to the yard tracks after the strain of many cycles of operation, and as a result the dumper may be rendered inoperative becauseof interference between the tracks or because the cars are derailed when rolled on or oit the dumper. However, the particular structure of the new car dumper assures that it can withstand the weight ofthe cars. In addition, means are provided to minimize impactstresses during the cycle of operation and to isolate the' stresses set up by the expanding suspension springs of the car so that they cannotk compound the load and cause serious strain.

Another critical factor in car dumper failure is the dimensional changes which result from extensive temperature variations during operation. When added to the strains mentioned previously, these thermal dimensional changes can seriously disrupt the operation of the dumper, particularly in many mining areas where rotary dumpers for unloading ore cars are expected to function under rapid and extensive changes in temperatures. Several novel features have therefore been incorporated into the new dumper to compensate for such dimensional changes caused by temperature variations.

In addition to protect the dumper structure from damaging stresses and strains, the present invention also provides means for accurately positioning the car-supporting platen both longitudinally and laterally relative to the yard tracks at the completion of each unloading cycle; Thus, the platen is movable longitudinally and laterally relative to its cradle to be properly centered by the positioning means.

In accordance withV the invention, a rotary car dumper is provided wherein a car is moved from stationary tracks to movable tracks normally aligned therewith on arplaten supported within a rotatable cradle. The improved structure comprises a plurality of rockers supporting the platen 3,116,843 Patented` Jan. 7, 1964 and pivoted on the cradle to permit longitudinal and lateral displacement of the platen relative to the cradle. A side bumper in included on the cradle against which the car rests upon lateral displacement of the platen during rotation of the cradle. Locking means are provided for holding the platen relative to the cradle after the car comes to rest against the bumper.

The improved structure also includes means for supporting the car upon rotation-of the cradle. These means comprise a plurality of clamping members and a plurality of barssupportingthe clamping members and slidably mounted to move them between positions retracted from and in engagement'with the car. A plurality of releasable locking devices are employed for holding the respective bars and clamping members substantially fixed relative to the cradle in the car-supporting position. Each of theselocking devices includes a locking shoe in surfaceto-surface engagement with its associated bar. A sprag member pivotally abuts the locking shoe to toggle ther shoe into locking engagement with the bar when the car exerts a load on the bar. A linkage is also included for displacing this sprag member and releasing the bar.

A further feature of the improvedy structure is that it includes avstationary stop engageable withthe platenupon rotation of the cradle into upright position to laterally displace the platen on the rockers and realign the tracks. Also, repositioning means are included for longitudinally displacing the platen on the rockers to bring the movable tracks into proper longitudinalposition upon rotation of the cradle into upright position.

There are several advantages which result from the irnproved means for supporting the car during rotation of the cradle. For example, each clamping member acts independently so thatpositive clamping is assured even though there maybe rocks or dirt lodged between one or more of the clamping members and the car. If such piecesindividually gripped by its own lockingrdevice so that failure of one would'not leave the car unsupported during.

rotation of the cradle. Each-locking device is designed to rely upon the loadrexerted on the clamping members in order to lock its associated clamping member relative to the cradle.

The locking means which hold the platen relative to` the cradle after the car comes to rest against the bumperserved to relieve the car. from a considerable portion ofl the stress exertedon it as the loaded car is rotated in the dumper. Otherwise, the weight of the platen compounded by certain spring forces would be supported entirely by the wheel flanges on the high side of the car about midway in its inversion. After the car has been loaded and the cradle returns to upright position, the platen andcar are. movedlaterally into realignment with the stationary tracks by. means of the stop elementwhich gently guides the platen into position during the last few. degrees of rotation of the cradle. Therefore, during rotation beforeV and after unloading, the platen is moved laterally back and forth without subjecting the structure to severe impact stresses which might otherwise cause critical dimensional strain.

By mounting the platen for longitudinal movement on the rockers and by including thel repositioning means for longitudinal displacement of the platen after unloading, assurance is provided that the movable tracks on the platen will not interfere with the stationary yard tracks. Also, this permits the platen to be locked in normal positic-n relative to the pit walls so that reaction to starting and stopping is taken up by the concrete walls and not entirely by the cradie structure.

Also, each clampingy member is,

A preferred embodiment of the new car dumper is described below with reference to the accompanying drawings, wherein FIG. l is an elevation partly broken away and in section of the new rotary car dumper;

FIG. 2 is a plan view partly broken away of the apparatus of FIG. 1;

FIG. 3 is a section taken along the line 3 3 of FIG. l;

FIG. 4 is an enlarged fragmentary section taken along the line 4 4 of FIG. 3;

FIG. 5 is an enlarged fragmentary vicw partly in section of the rockers supporting one movable platen;

FIG. 6 is a fragmentary section taken along the line 6 6 of FIG. 5 and showing the longitudinal rockers;

FIG. 7 is a fragmentary section taken lalong the line 7 7 of FIG. 5;

FIG. 8 is a fragmentary section taken along the line d S of FIG. 5 and showing the lateral rockers;

FIG. 9 is an enlarged fragmentary section taken along the line 9 9 of FIG. l;

FIG. 10 is an enlarged fragmentary section of the platen brake means;

FIG. 11 is a fragmentary elevation of the means for longitudinally and laterally readjusting the pos-ition of one platen on its rockers;

FIG. 12 is a fragmentary section taken along the line 12 12 of FIG. 11;

FIG. 13 is an enlarged fragmentary section taken along the line 13 13 of FIG. 12;

FIG. 14 is an enlarged fragmentary `section taken along the line M M of FIG. 11;

FIG. 15 is a section taken along the line 15-15 of FIG. 1 and showing the car clamping means;

FIG. 16 is a fragmentary section taken along the line 16 16 of FIG. 15;

FIG. 17 is an enlarged fragmentary section taken along the line 17-17 of FIG. 16 and showing in detail the locking devices and their actuating means;

FIG. 18 is an enlarged fragmentary section taken along the line 5E-1S of FIG. 17;

FIG. 19 is an enlarged fragmentary section taken along the line 1.9 19 of FIG. 17; and

FIGS. 20 through 25 are diagrammatic cross sections f the car dumper in various positions from the upright starting position to the fully unloaded position where the car is substantially inverted.

Referring iirst to FIGS. l, 2, and 3, the new rotary car dumper is shown in an operative position within a pit 36. The bottom of the pit opens in the direction indica-ted at 3l and 32 into hoppers into which the material is to be dumped. Leading up to edge of the pit at the left as seen in FIG. 1 is a yard track 33 along which the loaded cars are moved toward the dumper. At the opposite end of the pit, a second yard track 34 leads away from the pit to carry the empty ears after they have been unloaded.

As shown most clearly in FIG. 3, the domper includes a base structure 35 :which extends throughout the floor of the pit in line with the yard tracks 33 and 3d. In the embodiment shown, two rotatable cradles, indicated generally at 36 and 37, are supported on the structure 35 to receive two loaded cars at one time. Each of the cradles 36 and 37 is rotatably supported on four heavy roller assemblies 38. Each roller assembly includes a large main axle 39y mounted on the structure 35. A beam 4t? is rotatably mounted about the axle 39 and in turn supports two secondary axles 41 and 42. The secondary axles 41 and 42 rotatably support rollers i3 and 44 respectively which ride on a peripheral rail formed about one of two large circular end frames IS-fi and 137-48 on the respective cradles 36 and 37. Hence, each of the cradles is adapted to rotate independently on its four roller assemblies 3S.

rDriving means are included for rotating the cradles 36 and 37 as shown in FIGS. 2 and 3. They include a large two-directional electric motor 5t) mounted in the pit 3? and positively geared to a primary drive shaft 511 extending along side both cradles. At the opposite ends of the primary drive shaft 51, it is geared to secondary drive shafts 52 and 53 associated with the cradles 36 and 37 respectively. The second-ary drive shaft 52 rotates Winches 54 and 5S at its opposite ends and the secondary drive shaft 53 rotates Winches 56 and 57 in a similar manner. Cables SS and 59 extend from the Winches 54 and 55 rcspectively about suitable grooves formed in the periphery of the circular end plates and 46 of the cradle 36. Similarly, cables 60 and 61 extend from the Winches 56 and 57 respectively about suitable grooves in the circular end plates 47 and 48 of the other cradle 37. By this construction, the motor 5@ is adapted to rotate the Winches and turn the two cradles 36 and 37 on the roller assemblies 38. If one cradle happens to lead the other during rotation, adverse stresses -are not set up because both cradles are driven by their own secondary drive shaft. Maximum rotation of the two cradles is limited by stops 62 and 63 (FIG. 3) on each circular end plate of both cradles which are adapted to engage one of the rollers on the roller assemblies 3-8 when the cradles reach upright or inverted position.

In FIG. 3, a railway car 64 is shown in dotted lines on tracks 67 supported on a platen 68 within the cradle 36. Also, the cradle 37 includes tracks 65 mounted on a platen 66 to support another of the railway cars 64. In upright position, the tracks 65 and 67 should be Ialigned with one another and with the yard tracks 33 and 34 leading to and from the dumper. To permit such alignment, the platens 66 and 68 are movably supported on their cradles for both longitudinal and lateral displacement.

One unit of the new platen-supporting means is represented by the rocker assembly shown in FIGS. 5 through 8 which is one of several such assemblies supporting each platen in each cradle. Interconnecting the circular end plates 47 and 48 of the cradle 37 are a number of Hoor beams 7e?. Rotatably mounted on one ofthe beams 76' is a pair of rockers 71 and 72 having arcuate toothed portions in engagement with a rack gear 73 rigidly mounted on a carriage 74 extending laterally beneath the platen 66. The carriage 74 rotatably supports a pair of lateral rockers 75 and 76 having arcuate toothed portions in engagement with respective rack gears 77 and 7S mounted on the underside of the platen GS. By these means, the platen is adapted to move longitudinally with respect to the cradle on its rockers 71 and 72 and laterally on its rockers 75 and 76. There are several of these rocker assemblies along the length of each platen so that both platens are fully supported and yet can move independently of one another.

A line of compression springs 80 are biased between a portion of each cradle and each of the platens 66 and 68 such that they urge the platens laterally on their rockers 75 and 76 to the right as shown in FIG. 5. In the upright position of the cradles these springs 80 urge the tracks 65 and 67 into alignment with the yard tracks 33 and 34. Once the cradles begin to rotate, however, the springs 80 are free to move the platens 66 and 68 to the right as shown in FIGS. 3 and 5 until the car 64 on each platen rests against respective bumpers 81 on cach of the cradles 36 and 37.

In order to reduce the stress on the cars 64, platen locking means are provided as shown in FIG. 5 and in detail in FIG. l0. One of these locking means is associated with each of the roller assemblies 38 supporting the respective cradles. Each locking means includes a pawl member 82 pivoted to its associated cradle immediately beneath the platen. This pawl member includes a pendulum arm and weight 83 extending at an angle relative to the pawl member such that the weight 83 holds the pawl member 82 away from the platen (as shown in FIG. 5) when the cradle is in upright position.

when the cradle is upright.

`the cradle in the early stages of rotation of the dumper and -the weight of the platen plus the force of the springs 80 is'taken from the wheel ilanges on the high side of the car during rotation. When the cradle returns to upright position after the car has been unloaded, the weight l83 swings the pawl member out of engagement with the rack member 84 and the platen is unlocked.

Referring now to FIGS. 3 and 11 through 14, means are shown for automatically positioning Ithe platens 66 and-68 such that their tracks 65 and 67 are longitudinally and laterally aligned with respect to'one another and to the yard tracks 33 and 34. The lateral 4positioning means includes a stop 86 aixed to andl extending outwardly from each end of `the pit 30 adjacent the remote ends of the two platens 66 and 68. Depending from the respective platens adjacent the stops 86 are brackets 87 each of which has a roller 88 rotatably mounted at its lower end. When the cradles return to upright position after unloading, these rollers -88 engage the corresponding stops 86 Well before the cradles reach full upright position. Consequently, further lateral movement of the platens is prevented by the stops and the platens therefore move laterally relative to their cradles and compress the springs 80.

By properly locating the rollers 88 on the platens and the stops 86 on the wall of the pit, both platens are urged v gently into proper lateral alignment with one another and with the yard tracks 33 and 34 at the end of the unloading cycle. Conversely, lat the beginning of the unloading cycle, the rollers 88 remain in engagement with their stop 86 during the first few degrees of the rotation of the cradles while lthe springs 80 expand and move the platens relative to the cradles toward the bumpers 81. This greatly reduces the impact of the cars 64 on the bumpers 81 since they approach at a relatively slow rate dependent upon the rate of rotation of the cradles.

At the remote ends of the two cradles 36 and 37 adjacent Athe yard tracks G3 and 34 respectively are longitudinal repositioning means as shown in FIGS. l2 and 14. That associated with the cradle 37 is described herein since the longitudinal repositioning means on the cradle 36 is exactly the same. Extending outwardly from the circular end plate 47 near its periphery is an arm 90 which comes into engagement with a roller 91 on a bell crank 92 during the last Vfew degrees of rotation of the cradle 37 into upright position. The bell crank 92 is pivotally mounted on the floor of the pit 30. The limits of movement of the bell crank 92 are shown in FIG. 12 in solid and dotted lines. A portion 93 thereof drives a rod 94 to which it is pivoted and which extends upwardly to a point adjacent the yard tracks 34 yand the end wall of the pit 30.

Near the upper end of the rod 94 and mounted on the pit wall is a positioning block 95 which is slidable relative to the wall on posts -96 (FIG. 14). Another block 97 is also slidably mounted on the posts 96 but is separated from the rst block 95 by a heavy compression spring 98. Between the irst block 95 and -a stationary plate 99 aflxed to the pit wall is a wedge member 100 which is aixed to the upper end of the rod 94. The tapered surface of the wedge member 100 is in surface-to-surface engagement with a correspondingly tapered surface of the block 95 so that when the rod 94 moves upwardly it forces the wedge member 100 between the plate 99 and block 95 and moves lthe block 95 toward the platen 67 of the cradle 37. A block 101 is mounted on the platen 67 to most advantageous spacing at that point.

6 be engaged by the block 97 after the spring 98 has been compressed and the block 97 is moved forwardby the wedge member 100.

Hence, the arm on the cradle 37 actuates the rocker arm 92 during the last few degrees of rotation of the cradle 37 and thereby forces the wedge member 1001 upwardly to bring theblock 97 into resilient engagement with the block 101 on the platen. This causes the platen 67 to be longitudinally displaced a limited amount on its rockers 71 and 72. By these means, each of the platens 66 and 68 is moved inwardly toward the center of the pit 30 during-the last few degrees of-rotation of the cradles 36 and 37. Thisprevents the tracks 65 and 67 on the platens `from interfering with the yard tracks 33 and 34 but spaces them closely relative thereto. It also prevents interference between the ends of the tracks 65 an'd.67 at the center of thedumper and establishes the In addition this mechanism locks the upright cradles relative to the pit so that the reaction of starting and stopping is absorbed by the pit walls and not the dumper structure.

Referring now to FIGS. 1 and v15 through 19, means are shown for supporting the car during rotation of the cradle. In FIG. 1, two car-supporting assemblies 103 and 104 are .associated with the cradle 36 and similar assemblies 105 =and 106 are associated with the cradle 37. Each Vof these assemblies is adapted to hold the car on both sides at one end thereof so that means are provided for holding each car at its four corners. Since the assemblies 10B through 106 are of identical construction they are described herein -with reference'only to the assembly 103 on the cradle 36, `as shown in detail in FIGS. l5 and 19.

The assembly 103 includes two clamping members 108 and 109 on opposite sides of the cradle 36. These clamping members are mounted on respective bars 110 and 111 which at their upper endsvinclude carriages 112 and 113 slidably mounted in suitable ways in the sides of the cradle structure. By these slidable mountings, the clamp-ing members are adapted to move between positions retracted from (as shown in FIG. 15) and in supporting engagement with the car 64 within the cradle. The clamping member 109 extends rigidly from the associated carriage 113. A-s explained previously, the car 64 rests against the bumper 81 during rotation of the cradle and in doing so its upper edge extends beneath the clamping member 109.

Such lateral movement of the car 64 displaces it away from the opposite clamping member 108 Iand thus that clamping member must 'extend further out toward the center of the .cradle to engage the other upper edge of the car 64. Since the clamping member 10S must extend far out when in clamping position, it might interfere with the locomotive or car as they move onto the cradle initially, and .thus means are provided for withdrawing the large clamping member 10S `away'from the center of the cradle when it is in retracted position. Accordingly, the clamping member 108 is pivoted about a pin 115 on its associated bar carriage 112. A-n integral .arm extends upwardly from fthe member 108 and supports a roller 116 Vat its outer end. Aixed to the cradle structure is a cam plate 117 which is disposed at an angle above the clamping member 103 to engage the roller 116 when the clamping member is moved upwardly into its retracted position. This causes the clamping member to pivot about a pin and swing away from the center of the cradle into the position shown in FIG. 15. As the clamping member 108 is lowered by the bar 110into car-supporting position, a roller 118 on the clamping member engages another cam plate 119 to swing the clamping member outwardly over the upper edge of the oar. i

.Both bars 110 and 111 extend downwardly below the iloor beams 7 0'of the cradle 36 and in the upright position of the cradle are supported at their lower ends by pins 120 and 121 respectively. These pins are movable to allow the bars and clamping members to be lowered into oar-supporting position. However, in order to urge the clamping members into car-supporting position without relying upon gravity, the bar carriages 112 and 113 are always urged `in that direction by counterweights 122 and 123 respectively. (Advantageously, each counterweight may comprise two weights adapted to act together on their associated bar as shown in FIG. l.) The counterweight 122 is supported by a cable 124 which is wrapped around pulleys 125 and 126 and is connected at 127 to the bar 110. Similarly, the ycounterweight 123 is supported by a cable 129 which is wrapped around pulleys 13th and 131 and is attached at 132 to the bar carriage 113. Each of these pulleys is rotatably mounted on the structure of the cradle 36. By these means, the clamping members 103 and 109 are urged toward car-supporting position notwithstanding the orientation of the cradle and the direction of gravitational forces.

The means for lowering the pins 12th and 121 and clamping members into car-supporting position are shown clearly in FIGS. l and 17. Tlhese include a cam roller 134 rotatably mounted in a stationary journal on a portion of the pit tloor. A follower arm 135 is pivotally mounted about a pin 136 supported on a portion 137 of the cradle structure. At the end of the arm 135 remote from the pin 136 is a cam surface 138 which engages the cam roller 134 when the cradle 36 moves into upright position. `During such engagement with the roller 134, the arm 135 is thereby forced into `the solid line position shown in FIG. 17. During the initial degrees of rotation of the cradle 36, the arm 135 moves clear of the roller 134 and pivots into the dotted line position shown in FIG. 17.

The pin 120 supporting the bar 110 is mounted rigidly on the arm 135 so that when the arm moves off the roller 134 into the dotted line position in FG. 17 the pin 120 moves with it and permits the clamping member S to be moved into car-supporting position by its counterweight 122. The other bar-supporting pin 121 is mounted rigidly on another arm 140 which is pivoted about a pin 141 on the structure of the cradle 36 and which is pivotally connected to the arm 135 by an intermediate link 142. By this construction, the arm 140 is drawn downwardly by the link 142 which moves with the Iarm 135 during the initial rotation of the cradle. Consequently, the arm 140 pivots into the dotted line position and thereby displaces the bar-supporting pin 121 and permits the other clamping members 159 to be moved into car-supporting position by its connterweight 123.

When the cradle 36 `is substantially inverted, the weight of the car 64 is Ialmost entirely supported by clamping members. Thus, releasable locking devices 144 and 145 are provided for locking the clamping members and their respective bars relative to the cradle. Each of these locking devices is supported substantially entirely by its associated bar but does not firmly lock its bar until after the clamping members have moved downwardly into engagement with the car. This is because there is a gap 146 between the frame of the locking device and the floor of the cradle. Consequently, the locking devices 144 and 145 are permitted limited movement relative to the cradle structure 36. This permits the car-supporting assemblies to compensate for the expansion of the suspension springs in the railway oars because the gap 146 is greater than the distance the wheel carriages are moved up by the springs when the car is inverted and unloaded.

Since the locking devices 144 and 145 are similar in construction, only the device 144 will be described. A backing shoe 149 is aiixed to the frame of the locking device 144 and is in surface-to-surface engagement with the bar 110. Opposite the backing-shoe 149 is a movable locking shoe 150 which is also in -surface-to-surface engagement with the bar 110. The locking shoe 150 is supported 'by a sprag member 151 which has a rounded 8 nose vseated within a corresponding seat on the back-side of the locking shoe opposite the bar 110. At the end of the sprag member 151 opposite the locking-shoe 150 is a similar round nose which is seated within another corresponding seat in a plate 152 mounted rigidly with respect to the frame of the locking device 144. Provision may be made to place shims between the plate 152 and the frame of the locking device to maintain the sprag member 151 at its proper position relative to the bar 110.

A compression spring 153 is biased between an adjustable screw plate 154 (FiG. 18) in threaded engagement with the frame `of the locking device. The spring 15.3 Urges the sprag member 151 about its pivotal engagement with the plate 152 in a clockwise direction as seen in FiG. 17. However, the length of the sprag member 151 is sligntly greater than the distance between the plate 152 and the locking shoe 150 so that the sprag member can be forced by the spring 153 not further than the angled position shown in FlG. l7. Thus, the locking shoe 156 is toggled against the bar 110. lt is apparent that an upward force in the bar 11G as seen in FIG. l7 4tends to wedge the locking shoe `150 tightly against the bar and also against the backing shoe 149 and thereby prevents the bar from moving relative to the locking device 144.

ln order to release the locking device 144 an arm 155 projects rigidly from the sprag member 151 and is pivotally connected at its outer end to a rod 156. The opposite end of the rod 156 is pivotally connected to a bellcrank 157 which is pivoted about a pin 15S amxed -to the cradle structure 36. Similarly, an arm on the sprag member of the other locking device 145 is pivotally connected to a second rod 159 which is pivotally attached to 1157', the opposite end of the bell-crank 157. By these means, rotation of the bell-crank 157 in a counter-clockwise direction as shown in FIG. 17 pivots the sprag member 151 downwardly against the force of the spring 153 and thus releases the locking shoe 151i from the backing `shoe 149. This unlocks the rod 11).

The bell-crank 157 is turned in this manner by a yoke 160 keyed to the pin 15S and spanning arms 161 and 161 which extend rigidly from the bell-crank 157. The yoke 160 is attached integrally to a lever 162 which is actuated by a rod 163. Motion of the rod 163 to the right as shown in FIG. l7 is resisted by a compression spring 164 which normally urges the bell-crank 157 into locked position. Hence, the rod 163 turns the yoke 169 through some degree of lost motion until the latter engages the arms 161 and 161 of the bell-crank 157. When the bellcrank i157 turns, both the rods 156 and 159 move to open the locking devices.

At the opposite end of the rod 163, it is pivoted to a lever 165 which is rotatably mounted about a pin 166 aiiixed to the cradle structure. The other end of the lever 165 supports a roller 166 which is adapted to engage a cam plate 167 (FIG. l5) mounted on a portion of the pit door. The configuration of the cam plate 167 is such that it deflects the lever 166 and holds the locking devices open during the initial stage of rotation of the cradle. When the clamping members move into car-supporting position, however, the cam plate 167 is cleared by the roller 166 so that the compression springs 153 move the locking devices into locl-:ed condition.

The operation of the new rotary car dumper will be described with reference to all of the drawings but particularly to FiGS. 20 through 25 which show various positions of the cradle structure. Initially, the cradles .36 and 37 are upright and their tracks 65 and 67 are aligned with one another and with the yard tracks 33. Two loaded railway cars 64 are wheeled from the yard tracks 33 onto the dumper such that one car is supported on the crade 36 and the other is supported on the cradle 37. During this initial movement of the cars onto the dumper, the clamping member 103 is retracted as shown 9 in FIG. l5 so as not to interfere with the locomotive which may be used to move the cars.

No `furtherpreparationis required once the cars are on the cradle. Hence, the drive motor 50' may then be activatedrto rotate the primary and secondary drive shafts so that the Winches S4-57 are operated to turn the cradles in a clockwise direction as seen in F-IGS. 3 and 15. In the unlikely event that the cradles 36 Iand 37 begin to turn at an unequal rate such that one leads the other, serious torsional stresses are not transmitted through the drive means because each cradle is driven by its own secondary drive shaft.

In moving through the first few degrees of rotation from the position shown in FIG. to that sho'wn in FIG. 2l, several operations are performed by the dumper mechanism. They will be described here with reference to the cradle 36 but it is to be understood that the Voperations are also performed on the other cradle. The very first movement of the cradle causes the compression springs 80 to move the platen 68 laterally on its lateral rockers l75 and '76 as the roller 88 on the bracket y87 remains in contact with the stationary stop 86. Thus, the car and platen move gently relative to the cradle at Va rate determined by the rate of rotation of the cradle toward the bumper S1. This minimizes the shock which otherwise would occur when the car engages the bumper.

To further reduce the stress on the structure, the pawl member 8-2 swings relative to the rotating cradle structure until it positively engages the rack member 84. This occurs at substantially the same time the car reaches the bumper 81 so that some of the weight of the platen is absorbed by the pawl member. Thus, the pawl member serves to lend support to the wheel lflanges of the car during the further stages of rotation.

During these initial stages .of rotation, the clamping means are also operated as the car moves toward the bumper. The arm 135 rides off the cam roller 134 and moves the rollers 120 and 121 generally downwardly and away from the underside of the cradle iioor. This permits both bars 11() and 111 which support the clamping members to be urged toward car-supporting position by the counterweights 1-22 and \123. As the clamping member 10@ moves downward, its roller 116 travels alongr the plate 117 and then moves away from it so that the roller 11S on the plate 1119 swings the clamping member about its axis 115 and into the extended car-supporting position.

While the clamping members are moved toward carsupporting position, the Iroller 166 on the lever I165 travels along the cam plate 167 to hold the locking device in open position. This allows the bars 110 and 111 to move toward car-supporting position as described. Once the carsupportin-g position has been reached, the roller 166 leaves the cam plate 1167 so that the compression springs 153 acting on the sprag members 151 cause the locking devices to move into clamped position. Thus, the locked shoes liti` are toggled against the associated bars.

When these operations have been accomplished the dumping apparatus is in the position shown schematically in FIG. 2l. In moving from the FIG. 21 position to that shown in FIG. 22, no further operations are performed except that more of the weight of the car is shifted to the bumper 81 and to the pawl member V82. It is to be noted that the position of the pulleys 125, 126', 130* and 131 is such that the clamping members continue to be urged toward car-supporting position by the counterweights 122 and l121" regardless of the orientation of the cradle. `If any debris, such =as dirt or rocks or the like, is lodged between a clamping member and the edge of the car and is later dislodged, the counterweights quickly displace the clamping member into car-supporting position and the rods 110 and 111 will slide through the unidirectional clamping devices f144` and 145.

After the dumper moves from the 90 position shown in FIG. 23 to the position shown in FIG. 24, a considerable proportion of the weight of the car is transferred 1 0 to the various clamping members. It is during this stage of rotationthat the bars 110 and 111 pull the locking devices :1744,and '145 against the cradle under the weight of the car to close the gaps145 and `147 which had existed between the locking devices and the floor beams of the cradle.

At'about the same time, the weight of the car leaves its wheels so that its suspension springs tend to ,force the wheel carriages in what is now an upward direction. Howeverythe ,expansion of the suspension springs cannot stress the cradle structure because the clamping members have vmoved away from the platen tracksa distanceequal to the gaps'1j45 and 147 and this distance is great enough so that the wheels of the railway car are left slightly olf the tracks.

The dumper proceeds to about the position shown in FIG. 25 where rotation is stopped by selective or automatic deactivation of the drive motor l50. The material contained in the car falls freely onto thehoppers 31 and 32 in the floor of the pit 30. It is to be noted that even in this position of the dumper, the counterweights 122 and 123 continue to urge the clamping members toward car-supporting position.

When the cars are unloaded, the motor 50 is activated inthe opposite direction such that the cradle rotates in a counter-clockwise direction as shown in FIG. 15. Thus,

`the dumper passes `through the position shown in FIGS.

24 and 23 and then the car settlesonce again onto the platen tracks. The counterweights 122 and 123 force the clamping members along with it so that thelocking devices l144 and VV145 again move away from the underside of the iloor beams and reopen the. gaps 146 and 147.

As the return motion continues from the FIG. 22 position `back toward the position shown in FIG. 2l, the various mechanisms again go into operation. First, the pawl member 82 leaves the rack member 84 to free the platen. The roller l166 on the lever 165 engages the cam plate 167 to rotate the bell-crank 157 in a direction such that it opens the locking devices which hold the clamping members. Also, the arm 135 engages the cam roller 134 to move both rollers 120 and 121 upwardly such that the clamping members are returned to retracted position. In such position, the clamping member 108 is dellected by the cam plate 117 into its withdrawn position.

During these last few degrees of rotation of the cradle, the longitudinal and lateral repositioning means go into operation. The roller 88 on the bracket 87 engages the stop S6 to prevent further lateral movement of the platen. The platen thus moves relative to its cradle against the compression springs and swings gently into laterally aligned position. Also, the arm on the cradle contacts the roller 91 on the bell-crank 92 and the wedge member is forced upwardly between the plate 96 and the block 95. Since this wedging action occurs at the remote ends of both cradles, the two platens 66 and 68 are moved slowly toward one another. The platen rails thereby clear the ends of the yard tracks 33 and 34 as the dumper arrives at upright position and they are properly spaced and aligned relative to one another at the center of the apparatus. Such longitudinal and lateral repositioning of the platens provides assurance that the railway cars can be wheeled from one platen to the other and onto the yard tracks without risk of derailment even when severe temperature variations cause appreciable dimensional changes in the dumper structure.

I claim:

l. In a rotary car dumper wherein a car is moved onto a platen supported within a cradle which is rotatable on a base, means for supporting the car upon rotation of said cradle comprising a plurality of clamping members, a plurality of bars supporting the respective clamping members and slideably mounted to move them between positions retracted from and in supporting engagement with said car, a plurality of releasable locking devices for holding the respective bars and clamping members substantially fixed relative to said cradle in their car-supportl l ing position, each of said locking devices including a locking shoe in surface-to-surface engagement with its associated bar, a sprag member pivotally abutting said shoe and said cradle to toggle said shoe into locking engagement with said bar when the car exerts a load on this bar, and linkage means for displacing said sprag member and releasing said bar.

2. A rotary car dumper according to claim l wherein each of said locking devices is supported by its associated bar in the upright position of said cradle and is movable with the bar to a limited extent relative to said cradle, and wherein abutting members are included on said cradle for supporting the respective locking devices and the bars axed thereto during rotation of said cradle.

3. A rotary car dumper according to claim 1 which includes counterweight displacement means for forcibly urging each bar and clamping member toward car-supporting position, tirst cam means on said base, associated first follower means on said cradle in operative engagement with said linkage means, said iirst follower means being displaceable by said rst cam means to unlock the locking devices when said cradle rotates from upright position, second cam means on said base, associated second follower means on said cradle engaging said bars, said second follower means being displaceable by said second cam means when said cradle rotates from upright position to permit said bars to be moved into car-supporting position by said counterweight displacement means, said iirst and second cam and follower means being adapted respectively to unlock said locking means and retract said bars and clamping members when said cradle returns to upright position.

4. A rotary car dumper according to claim 3 wherein the clamping members on one longitudinal side of said platen are pivotally mounted on their respective bars, cam plates mounted on said cradle in the path of travel of the respective pivotal clamping members, said plates being l2 adapted to be engaged by said pivotal clamping members and to pivot them away from the car when said bars move into retracted position.

5. In a rotary car dumper wherein a car is moved onto a platen supported within a rotatable cradle, means for supporting the car upon rotation of said cradle comprising a plurality of clamping members, a plurality of bars supporting the respective clamping members and slideably mounted to move them between positions retracted from and in supporting engagement with said car, a plurality of releasable locking devices for holding the respective bars and clamping members substantially fixed relative to said cradle in their car-supporting position, each of said locking devices comprising opposed locking and backing shoes in surface-to-surface engagement with opposite sides of the bar, a sprag member pivotally abutting said locking shoe and said cradle, spring means biasing said sprag member to urge said locking shoe forcibly against said bar, whereby in the inverted position of said cradle the load on said bars locks them between their respective sprag-actuated shoes, and linkage means operative against the force of said spring means for displacing said sprag member and releasing said bar.

6. A rotary car dumper according to claim 5 wherein each of said locking devices is supported by its associated bar in the upright position of said cradle and is movable with the bar to a limited extent relative to said cradle, and wherein abutting members are included on said cradle for supporting the respective locking devices and the bars aixed thereto during rotation of said cradle.

References Cited in the file of this patent UNTED STATES PATENTS Kidder et al. May 26, 1931 

1. IN A ROTARY CAR DUMPER WHEREIN A CAR IS MOVED ONTO A PLATEN SUPPORTED WITHIN A CRADLE WHICH IS ROTATABLE ON A BASE, MEANS FOR SUPPORTING THE CAR UPON ROTATION OF SAID CRADLE COMPRISING A PLURALITY OF CLAMPING MEMBERS, A PLURALITY OF BARS SUPPORTING THE RESPECTIVE CLAMPING MEMBERS AND SLIDEABLY MOUNTED TO MOVE THEM BETWEEN POSITIONS RETRACTED FROM AND IN SUPPORTING ENGAGEMENT WITH SAID CAR, A PLURALITY OF RELEASABLE LOCKING DEVICES FOR HOLDING THE RESPECTIVE BARS AND CLAMPING MEMBERS SUBSTANTIALLY FIXED RELATIVE TO SAID CRADLE IN THEIR CAR-SUPPORTING POSITION, EACH OF SAID LOCKING DEVICES INCLUDING A LOCKING SHOE IN SURFACE-TO-SURFACE ENGAGEMENT WITH ITS ASSOCIATED BAR, A SPRAG MEMBER PIVOTALLY ABUTTING SAID SHOE AND SAID CRADLE TO TOGGLE SAID SHOE INTO LOCKING ENGAGEMENT WITH SAID BAR WHEN THE CAR EXERTS A LOAD ON THIS BAR, AND LINKAGE MEANS FOR DISPLACING SAID SPRAG MEMBER AND RELEASING SAID BAR. 